emmc: support CMD23
Support CMD23. When CMD23 is used, CMD12 could be avoided.
Two scenarios:
1. CMD17 for single block, CMD18 + CMD12 for multiple blocks.
2. CMD23 + CMD18 for both single block and multiple blocks.
The emmc_init() should initialize whether CMD23 is supported
or not.
Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
diff --git a/drivers/emmc/emmc.c b/drivers/emmc/emmc.c
index 5fe28ef..3fae2a1 100644
--- a/drivers/emmc/emmc.c
+++ b/drivers/emmc/emmc.c
@@ -40,6 +40,12 @@
static const emmc_ops_t *ops;
static unsigned int emmc_ocr_value;
static emmc_csd_t emmc_csd;
+static unsigned int emmc_flags;
+
+static int is_cmd23_enabled(void)
+{
+ return (!!(emmc_flags & EMMC_FLAG_CMD23));
+}
static int emmc_device_state(void)
{
@@ -174,11 +180,23 @@
ret = ops->prepare(lba, buf, size);
assert(ret == 0);
- memset(&cmd, 0, sizeof(emmc_cmd_t));
- if (size > EMMC_BLOCK_SIZE)
+ if (is_cmd23_enabled()) {
+ memset(&cmd, 0, sizeof(emmc_cmd_t));
+ /* set block count */
+ cmd.cmd_idx = EMMC_CMD23;
+ cmd.cmd_arg = size / EMMC_BLOCK_SIZE;
+ cmd.resp_type = EMMC_RESPONSE_R1;
+ ret = ops->send_cmd(&cmd);
+ assert(ret == 0);
+
+ memset(&cmd, 0, sizeof(emmc_cmd_t));
cmd.cmd_idx = EMMC_CMD18;
- else
- cmd.cmd_idx = EMMC_CMD17;
+ } else {
+ if (size > EMMC_BLOCK_SIZE)
+ cmd.cmd_idx = EMMC_CMD18;
+ else
+ cmd.cmd_idx = EMMC_CMD17;
+ }
if ((emmc_ocr_value & OCR_ACCESS_MODE_MASK) == OCR_BYTE_MODE)
cmd.cmd_arg = lba * EMMC_BLOCK_SIZE;
else
@@ -193,11 +211,13 @@
/* wait buffer empty */
emmc_device_state();
- if (size > EMMC_BLOCK_SIZE) {
- memset(&cmd, 0, sizeof(emmc_cmd_t));
- cmd.cmd_idx = EMMC_CMD12;
- ret = ops->send_cmd(&cmd);
- assert(ret == 0);
+ if (is_cmd23_enabled() == 0) {
+ if (size > EMMC_BLOCK_SIZE) {
+ memset(&cmd, 0, sizeof(emmc_cmd_t));
+ cmd.cmd_idx = EMMC_CMD12;
+ ret = ops->send_cmd(&cmd);
+ assert(ret == 0);
+ }
}
/* Ignore improbable errors in release builds */
(void)ret;
@@ -218,11 +238,24 @@
ret = ops->prepare(lba, buf, size);
assert(ret == 0);
- memset(&cmd, 0, sizeof(emmc_cmd_t));
- if (size > EMMC_BLOCK_SIZE)
+ if (is_cmd23_enabled()) {
+ /* set block count */
+ memset(&cmd, 0, sizeof(emmc_cmd_t));
+ cmd.cmd_idx = EMMC_CMD23;
+ cmd.cmd_arg = size / EMMC_BLOCK_SIZE;
+ cmd.resp_type = EMMC_RESPONSE_R1;
+ ret = ops->send_cmd(&cmd);
+ assert(ret == 0);
+
+ memset(&cmd, 0, sizeof(emmc_cmd_t));
cmd.cmd_idx = EMMC_CMD25;
- else
- cmd.cmd_idx = EMMC_CMD24;
+ } else {
+ memset(&cmd, 0, sizeof(emmc_cmd_t));
+ if (size > EMMC_BLOCK_SIZE)
+ cmd.cmd_idx = EMMC_CMD25;
+ else
+ cmd.cmd_idx = EMMC_CMD24;
+ }
if ((emmc_ocr_value & OCR_ACCESS_MODE_MASK) == OCR_BYTE_MODE)
cmd.cmd_arg = lba * EMMC_BLOCK_SIZE;
else
@@ -237,11 +270,13 @@
/* wait buffer empty */
emmc_device_state();
- if (size > EMMC_BLOCK_SIZE) {
- memset(&cmd, 0, sizeof(emmc_cmd_t));
- cmd.cmd_idx = EMMC_CMD12;
- ret = ops->send_cmd(&cmd);
- assert(ret == 0);
+ if (is_cmd23_enabled() == 0) {
+ if (size > EMMC_BLOCK_SIZE) {
+ memset(&cmd, 0, sizeof(emmc_cmd_t));
+ cmd.cmd_idx = EMMC_CMD12;
+ ret = ops->send_cmd(&cmd);
+ assert(ret == 0);
+ }
}
/* Ignore improbable errors in release builds */
(void)ret;
@@ -328,7 +363,8 @@
return size_erased;
}
-void emmc_init(const emmc_ops_t *ops_ptr, int clk, int width)
+void emmc_init(const emmc_ops_t *ops_ptr, int clk, int width,
+ unsigned int flags)
{
assert((ops_ptr != 0) &&
(ops_ptr->init != 0) &&
@@ -342,6 +378,7 @@
(width == EMMC_BUS_WIDTH_4) ||
(width == EMMC_BUS_WIDTH_8)));
ops = ops_ptr;
+ emmc_flags = flags;
emmc_enumerate(clk, width);
}